Process for the production of alkyl diaryl esters of ortho phosphoric acid



Patented Apr. 18, 1950 PROCESS FOR THE PRODUCTION OF ALKYL DIABYL ESTER/S OF OB'I'HO PHOSPHOBJC ACID Harry B. Gamrath, St. Louis, Mo, asslgnor to Monsanto Chemical Company, St. Louis, Mon a corporation of Delaware No Drawing. Application February I, 1949,

Serial o nr-o-i w-noi wherein R1 represent an alkyl radical terminat with a CH: group and containing at least 6 and not more than 18 carbon atoms or beta-alkoxyethyl radical wherein the alkyl substituent is an alkyl group of at least 4 and not more than 18 carbon atoms and R2 represents a phenyl, cresyl, or chlorophenyl radical. Herein when the phrase "monoalkyl diary] phosphate ester is used, it is the intention that the phrase include only such compounds as fall within the above definition.

This application is a continuation-in-part of copending application Serial No. 38,194, filed July 12, 1948, now abandoned, which is a continuationin-part of application Serial No. 720,310, filed January 4, 1947, now abandoned.

The monoalkyl diary] phosphate esters prepared by the novel process of this invention are generally nearly colorless liquids having mild pleasant odors. These esters have exceptional utility as flexibilizing plasticizers for polyvinyl chloride compositions, imparting to those compositions the combination of properties of flexibility at freezing temperatures. low volatility losses of plasticizer at higher temperature and non-infiammability. Because of their very low pour points and very high autogenous ignition temperatures and their compatibility with parailinic hydrocarbon oils, these monoalkyl diaryl phosphates may be used alone or in combination with parafllnic hydrocarbon oils to prepare hydraulic and torque converter fluids of highly desirable characteristics. Moreover, these esters have a wide variety of other uses, such as lubricants for mechanisms from deicate clock works to extreme pressure bearing surfaces, film-forming addition agents in hydrocarbon oils for use in extreme pressure lubricants and as a liquid medium for filters for air conditioning systems.

In all of the above mentioned uses of the monoalkyl diary! phosphate esters prepared by the novel process 01 this invention, it is to be emphasized that exceptional purity is required. For example, in their use as plasticizers for polyvinyl chloride, excessive quantities of the dlaikyl derivaidves decrease the permanence of the plasticizer in the plasticized composition. Excessive quantities of the triaryl derivative in such application cause a decrease in the flexibility characteristics of the plasticized composition. Moreover, such impurities cause substantial changes in the autogenous ignition temperatures of the monoalkyl diaryl phosphate esters and also substantial changes in the viscosity of the esters thereby seriously ailecting the utility of these esters as hydraulic and torque converter fluids.

Various methods are known for the production of esters of phosphoric acid, however, none of these methods or processes as described in the art have proven to be commercially feasible for the production of monoalkyl diary! phosphate esters of hi h purity. Furthermore, it has been foumi that several of these methods described in the art while possessing utilit in the preparation of certain types of esters of phosphoric acid do not lend themselves to the production of monoalkyl diaryl phosphate esters.

A common procedure described is that of reacting 2 mols of phenol or similar hydroxy aryl compound with 1 mo] of phosphorus oxychloride, removing the H01 formed under vacuum, and then reacting the dlphenyl phosphoryl chloride with 1 mol of an aliphatic alcohol. This procedure is objectionable as the reaction is difficult to control and excessive quantities of the-trlaryl derivatives are formed, resulting in an impure prodduct with low yields. Another procedure described is that of preparing the triaryl phosphates, removing one aryl group by alkaline hydroylsls followed by steam distillation and then introducing the alkyl group. The principal objectionable feature of this process is that it is exceedingly costly in view of the increased number of steps required to produce the finished product. A further method described is that of reacting in excess oi 1 mol of an aliphatic alcohol with 1 moi of phosphorus oxychioride, removing the HCl formed under vacuum, purifying the monoalkyl phosphoryl dichloride by distillation and subsequently reacting at a relatively high temperature the purified acid chloride with 2 mols of phenol 01 similar hydroxy aryl compound. According to this latter process, in order to obtain pure neutral phosphate esters. it is essential that the intermediate alkyl phosphoryl dichloride be separated from the reaction mixture and purified.

It is evident that methyl phosphoryi dichloride may be purified by fractionation inasmuch as no decomposition was found after 24 hours at l-110 C. and that its boiling point under 30 This is accomplished by fractional distillation of mm. vacuum, a commercially feasible pressure, is the acid chloride from the reaction mass. Pure 31 3} g: dglamp llin Bl glhiihlzzph l esters may also be obtained by iractionating the 0 e W P 06 c 0 8 y crude neutral phosphate esters. This process has many be fmflmted their fling mints given satisfactory results when the aliphatic aleommmmly feasible subatmwphem Preshol used was a primary alcohol of relatively short 10 sums a be reduced below their respective chain length. However, it is known that secondmp0s on tempemtm ranges- However it is ary. tertiary. and substituted alcohols are not evident that as the length M the alkyl chain is suited to this reaction. Typical alcohols which do g; :ndency a geczmpose is not satisfactorily undergo the reaction as *deeased w c sub-sum a d considering the scribed are the all?! or substituted aiiyl alcohols. mam Pmsphm" dmmmdesmm, a] 00h 018 Secondary butyl alcohol hem ah Thus it is evident from the extremely short decohol and fl-octanol. Moreover, it has been found 3%? g a g fi ghmphory] ch10 that monoallwl phosphoryl dichlorides tend todee a e 8 Vacuum compose with such decomposition being dependsaw reduce its mums point that it may be ant upon time and temmturm m the case of fractionated without decomposition, that a furthe lower alkyl phosphoryl dichlorides, such as the 3:5 m t: the g g g gg gi d i ci-ci eikwi phosphoryl dichlorides, the boiling h l m b Pdistm t points of the compositions are lower than their phosp c o e y a Consider respective decomposition temperature range unmg the phospmry] (chlorides which are der commercially practical subatmospheric pres- 95 m m i isg g a: gz z f g sure thereby permitting purmcauon of the mono of this inve tio it: is 52cc thgt 0021111811315 u? alkyl phosphoryl dichloride by fractionation. n u f id cm m h f u However, the decomposition temperature ranges i gg g g i y g of the monoalkyl phosphoryl dichlorides which he e hed d 8 no ti 0 ese m 1mm the form or the a; mi, alkvl diary] phosphate esters prepared by the novel mo in and Se a t f m d process of this invention are lower than their recomp n mac on p m on o e wave boiling points that could be obtained um composition products into two distinct layers. In der commercially feasible subatmospheric presgag ag fiz zzi fi zi fi i f fi igz lures thus rendering purification of the intermea my diate monoaliwl phosphoryl dichlorides by compmflcazlequipmelit would be necessary mercial fractionation impossible. Furthermore, m a f zsfi g gfi rg g fi i purmed mtemedme pmsphm" dichm' hosph l dichloride: because of their hi hi rides are obtained and subsequently reacted with gonoslfiamre and their tendenc to as g y hvdroxy aryl compounds to form monoalkyl di- 40 e y g m] phosphates the relatively high temperatures Butoxyethyl phosphoryl dichloride does not demum! the "weed 3311;: der fi'atives that an :x t i iermi d o s tially quantitatively are again higher than the position accompanied i a separation of the decomposition temperature ranges of the respecdecomposition products but on being subjected the and consequentm heat t hos n 1 ly decomposition again results. H p p m e We relationships that exist between the severely discolors, which coloration is evident in boiling point and the decomposition temperature 22 zrgz zigigg g ga fg range of various phosphor dlcmc'fldes are th elevated tem ratures used in the reaction shown on the following table wherein: e W

Column A is the am I i 1 th alkoxyethyl phosphoryl dichlorides with a hythermic decomposition fo ut who th: :12; m g fi g g g gi fi g 11101108- oxye a p osp a as w c ghosphoryl dichloride is maintained at 100-l10 m not suitable for the applications previously Colu n B is the bo s ran e when the mass In view oi the teachings of the art, one would emp r r i m in ned a 7 -80 0.. which is not believe commercial production of essentially a reasonably safe mass temperature in view of the pure monoalkyl diaryl phosphate esters would be exothermic decomposition characteristics. economically practical or feasible. First, con- Compound A n anate-.1 ire raises;

LM'I minutes 68-13'l0.5-08mm. 1.2106 No separation in i3 hrs. Severely blackons in about [-2 hours. n hoxyl phosphoryldichlm'ido 1.18m ill-min Diggnotdisti 'itlimasstempmtwundei' Winches ldlclilorldo him a? p S-ethyl xyln can ldi hlnrlda L132) Do. My] s s iuie lor' e um Do. nee, p B iuiehieriee 1.0m Do. IAnryI nhosphoryl dichlor-de 1. 0504 Do.

hos Idlchlorida.-- Loci: Do. Tetnd lghosp ldlchlorldo 1.0m Do. W p osphory do 0.9905 Do.

sidering the general resistance of secondary, tertiary or substituted alcohols to the formation of the corresponding alkyl phosphoryl dichlorode, it would not be expected that highly branched Cu to Cu; alcohols or alkoxyethyl alcohols wherein the alkyl substituent consists of an alkyl group of at least 4 and not more than 18 carbon atoms, would satisfactorily react with phosphorus oxychloride to form the monoalkyl phosphoryl dichloride. Secondly, in view of the teachings of the art, those monoalkyl phosphoryl dichlorides which could be prepared, could be formed only in limited quantities by reacting a considerable molar excess of the alcohol with phosphorus oxychioride. However, inasmuch as a pure alkyl phosphoryl dichloride is necessary to permit the production of a pure monoalkyl diaryl phosphate, the alkyl phosphoryl dichloride would have to be purified by fractionation before subsequent reaction with a hydroxy aryl compound and as previously pointed out in view of the decomposition characteristics of these alkyl phosphoryl dichlorides purification by fractionation would be impossible. Similarly any attempt at a quantitative reaction between a purified monoalkyl phosphoryl dichloride and a hydroxy aryl compound would also result in failure due to the high temperature necessary to cause the reaction to approach quantitative values also being higher than the decomposition temperature range of the acid chloride thereby causing decomposition of the reaction mass. Furthermore, it is obvious that the methods as heretofore practiced would yield esters containing considerable quantities of impurities which would necessitate purification by fractionation of the esters in order to obtain organic phosphate esters of sufllclent purity for utility in the applications discussed herein.

It is an object of this invention to provide an improved process for the production of monoalkyl diaryl phosphate esters.

It is a further object of this invention to pro vide an improved commercially feasible process for the production of high purity monoalkyl diaryl phosphate esters.

Moreover, it is an object of this invention to provide an improved commercially feasible process for the production of monoalkyl diaryl phosphate esters wherein the simple reactions of the process produce esters of such a high degree of purity that further purification by fractionation of the ester is unnecessary.

Still further objects will become apparent from the description of the novel process and the claims.

These objects are attained by the novel process of this invention by reacting under controlled conditions one molecular proportion of a Cu to Cu primary alkyl alcohol or beta-allroxyethyl alcohol. wherein the alkyl substituent consists of an alkyl radical of at least 4 and not more than 18 carbon atoms, with one molecular proportion of phosphorus oxychloride, while continuously removing the HCl formed under vacuum, thereby forming in essentially quantitative yields, requiring no further purification, the monoalkyl phosphoryl dichloride. This organic phosphoryl dichloride is then added under controlled conditions to substantially two molecular proportions of sodium arylate in an aqueous solution. monoalkyl diaryl phosphate thus formed in high yields is separated from the aqueous reaction mass, washed with water and dilute alkali and dehydrated under vacuum. The ester thus obtained is of such a high degree of purity that The resultant further purification by fractionation is unnecessary.

The high degree of purity of the esters obtalned is illustrated by the following elemental analysis of esters obtained by the novel procas of this invention.

The monoalkyl diaryl phosphate esters that may be prepared by the novel process of this invention are illustrated by the following compounds, although it is not intended that this invention be limited solely to the preparation of these compounds.

2-ethylbutyl diphenyl phosphate 2-methylpentyl dicresyl phosphate Octyl dicresyl phosphate 2-ethylhexyl dicresyl phosphate 2-ethylhexyl di-p-cresyl phosphate Iso-octyl dicresyl phosphate Iso-octyl di-p-cresyl phosphate 2-ethylhexyl diphenyl phosphate Octyl diphenyl phosphate Iso-octyl diphenyi phosphate Nonyl diphenyl phosphate Trimethylhexyl diphenyl phosphate Nonyl dicresyl phosphate Decyl dicresyl phosphate Dodecyl diphem'l phosphate Dodecyl dicresyl phosphate 2-n-propylheptyl diphenyl phosphate Hexoxyethyl diphenyl phosphate Butoxyethyl diphenyi phosphate 2-ethylbutoxyethyl dicresyl phosphate Z-methylpcntoxyethyl diphenyl phosphate n-Hexoxyethyl dicresyl phosphate 2-methylpentoxyethyl dicresyl phosphate Octoxyethyl dicresyl phosphate 2-ethylhexoxyethyl diphenyl phosphate Iso-octoxyethyl dicresyl phosphate 2-ethylhexoxyethyl dicresyl phosphate n-Octoxyethyl diphenyl phosphate Nonoxyethyl dicresyl phosphate Trimethylhexoxyethyl diphenyl phosphate n-Decoxyethyl dicresyl phosphate 2-n-propylheptoxyethyl dicresyl phosphate Decoxyethyl diphenyl phosphate Z-n-propylheptoxyethyl diphenyl phosphate Dodecoxyethyl diphenyi phosphate Dodecoxyethyl dicresyl phosphate Butoxyethyl di-m-cresyl phosphate 2 ethylhexoxyethyl di-m-cresyl phosphate Butoxyethyl di(o-chlorophenyl) phosphate 2-methylpentyl di(o-chlorophenyl) phosphate Z-ethylhexyl di o-chlorophenyl) phosphate Z-n-propylheptyl dl(o-chlorophenyl) phosphate Dodecyl di(o-chlorophenyl) phosphate Tridecyl diphenyl phosphate Tridecyl di-m-cresyl phosphate Tridecoxyethyl diphenyl phosphate Tetradecyl di(o-chlorophenyl) phosphate Tetradecyl di p-cresyl phosphate 76 Tetradecoxyethyl diphenyl phosphate In the above list of compounds, the nonyl and dodecyl radicals may be derived, in addition to the conventional sources, from the polymerization products of oleflns, such as propylene, or the dodecyl radical may be derived from the polymerization products of olefins such as butylene. These alkyl radicals may also be derived from branched chain primary alcohols prepared by the polymerization of oleflns to form a branched chain olefin, followed by the reaction with carbon monoxide and hydrogen (oxo process) to form a primary branched chain alkyl alcohol. Thus a nonyl alcohol may be prepared from the polymerization of isobutylene to form an octene which may then be reacted with carbon monoxide and hydrogen to form a branched chain primary ncnyl alcohol. Nonaldehyde may be prepared in a similar manner and may then be subjected to an aldol condensation to form a branched chain primary octadecyl alcohol. The alkyl radicals may also be derived from straight chain primary alcohols obtained by the hydrogenation of coconut oil and fats.

In the monoalkyl dicresyl phosphates which are intended to be prepared by the novel process of this invention, the cresyl radical may bean rthocresyl. para-cresyl, or meta-cresyl. Similarly in those compounds containing a chlorinated phenyl radical, the chlorophenyl radical may be an ortho-chlorophenyl, para-chlorophenyl, or metachlorophenyl radical.

EXAMPLE I z-ethylheryl diphenul phosphate Forty-six grams of POCh are cooled with stirring to about C. in a glass lined closed reaction vessel. Thirty-nine grams of Z-ethylhexanol which have been cooled to approximately 15 C. are added to the POCl; with continuous stirring and at a rate so as to maintain a reaction-mass temperature of about 15 C. The reaction mix: ture is agitated and the reaction temperature of 15 C. is maintained for one hour following the addition of all the 2-ethylhexanol, thereafter the temperature is allowed to rise to C. and the stirring continued for another hour. The hydrogen chloride gas which is evolved from the reaction is continuously removed by means of applying a vacuum to the reaction vessel. After the reaction between the 2-ethylhexanol and the P001; and the removal of the hydrogen chloride have been completed, the substantially pure 2- ethylhexyl phosphoryl dichloride is transferred to a reactor containing 250 g. of an aqueous solution, cooled to 0 0., having a composition of 32% sodium phenate. The 2-ethy1hexyi phosphoryl dichloride is added to the aqueous sodium phenafe solution at such a. rate as to maintain a temperature below 5'' C. After all the z-ethylhexyl phosphoryl dichloride has been added to the aqueous sodium phenate solution, the reaction mixphostime is agitated for an hour and then, with continuous stirring. allowed to warm up to room temperature. Themixtureisthenaiiowedtostand until an ester layer and an aqueous layer form; the ester layer is then separated from the aqueous layer. The ester is given successive washes with 2% NaOH solution and water and then dehydrated under vacuum at about C. The yield, based on POCh, was 91%.

The z-ethylhexyl diphenvl phosphate prepared in the above manner had the following properties:

8p. gr. 25/25 0.............. 1.090 N 1.510 Boiling point at 5 mm Approx. 232' C. Freezing point Below 0 C. Color Nearly water white Pour point. ---65 C. Viscosity 30 F 2167 centistokes Viscosity 100 F 10.1 centistokes Viscosity 210 PL. 2.46 centistokes Autogenous ignition temperature 10.50" F.

While specific quantities, temperatures and reaction conditions have been set forth in Example I, it is not intended that the novel process of this invention be restricted solely thereto as to a certain degree these quantities, temperatures and reaction conditions may be varied. Thus, in the first step of the reaction. that is the formation of alkyl phosphoryl dichloride, it is preferred that substantially one molecular proportion of the aliphatic alcohol be used for each one molecular proportion of phosphorus oxychioride. A slight variation is permissible however as the molecular proportion of the alcohol is increased beyond the preferred one molecular proportion. the formation of dialkyl phosphoryl chloride is promoted afiecting the yield and quality of the final product. If the molecular proportion of the alcohol is reduced below the preferred one molecular proportion, the yield of the finished product is reduced due to the presence of unreacted phosphorus oxychloride which must be removed by fractionation to prevent the formation of the triaryl derivative during the subsequent reaction.

The reaction between the alcohol and the phosphorus oxychloride is exothermic and is accompanied by a considerable evolution of hydrogen chloride. The rate of addition of the alcohol and the temperature at which the reaction mass is maintained is therefore governed by the nature of the equipment, cooling capacity and ability to remove hydrogen chloride as it is formed to prevent too violent a reaction. While it is preferred that the addition rate be so governed that the temperature may be maintained at substantially 15 C. it is evident that such a rate of addition and temperature will depend to a large extent on the nature of the equipment used and ability to control temperature to prevent loss of the reactants through volatilization.

The practical temperature range limits of this reaction are also governed by the freezing point of POCh and the color of finished product desired. Since POCI: crystallizes at approximately 2 0., initial reaction temperatures below 2 C. are not practical. Once the reaction is begun, the temperature may then be reduced below +2 C. as the alcohol added and the alkyl phosphoryl dichloride formed depress the crystallizing point of the mass so that lower temperatures may be maintained. As the temperature of the reaction is increased greater than 25 0., the color of the monoalkyl phosphoryl dichloride is increased resulting in more highly colored monoalkyl diaryl phosphate esters. Thus, the preferred and practical temperature range of this reaction is from about 2 C. to about 25 C. After the reaction is substantially complete, the temperature may be increased to a maximum of 50 C. to facilitate the removal of the hydrogen chloride gas evolved in the reaction.

It is also preferred that the alcohol be added to the POClz. While the reverse order of addition of reactants may be utilized, such a reverse order promotes the formation of the dialkyl phosphoryl chloride and trialkyl phosphate ester thereby affecting the purity of the final product.

The concentration of the sodium arylate solution is governed by the solubility of the sodium arylate at the temperature at which the reaction between the alkyl phosphoryl dichloride and sodium arylate is carried out. It is obvious that the concentration of the sodium arylate solution should approach the solubility limit of sodium arylate at the reaction temperature for economic and production reasons. However, it is also obvious that significantly lower concentrations may be used if desired.

It is preferred that two molecular proportions of sodium arylate be used for each one molecular proportion of alkyl phosphoryl dichloride with a maximum of 5% excess. If less than two molecular proportions of sodium arylate be used, the yield of the final product will be reduced. If greater than a 5% excess is used, purification oi the final product will be made more difficult in that excessive quantities of sodium arylate will have to be removed from the final product.

The temperature of the reaction between the sodium arylate and the monoalkyl phosphoryl dichloride is preferably between 0 and 25 0., however the reaction may be carried out from -l0 to substantially 50 C. If the temperature of the reaction is maintained at the higher level, however, the color of the final product is somewhat darker than that that would have resulted if the reaction had been carried out at 0 to 25 C. Maintaining a reaction temperature of less than 0 C. limits the concentration of the sodium arylate solution that may be utilized.

In carrying out the reaction between the monoalkyl phosphoryl dichloride and sodium arylate it is highly preferred that the monoalkyl phosphoryl dichloride be added to the sodium arylate solution in order to obtain a pure monoalkyl diaryl phosphate ester. Reversing the order of addition of the reactants invariably leads to hydrolysis with subsequent low yields of the finished product and the formation of a considerable amount of impurities.

The esters prepared by the novel process of this invention are of such a degree of purity, as heretofore mentioned, that purification by fractionation is unnecessary. Usually all that is required is a simple water and alkali wash followed by dehydration under vacuum. At times, however, it may be necessary to subject some of the more difllcultly purified esters to a simple steaming procedure to remove the last traces of the alcohol or other volatiles. This steaming operation can then be followed by dehydration in the normal manner.

If the alkyl phosphoryl dichloride is added to the sodium arylate at temperatures below C., the resulting phosphate ester is usually substantially colorless. However, the phosphate esters with more color may be treated by the conventional means well known to those familiar with the art to remove the undesirable color.

EXAMPLE II Nonyl diphenl/l phosphate 460.2 g. of P001: are cooled with stirring to a temperature of 5 to 10 C. in a glass lined closed reaction vessel. 432.8 g. of a nonyl alcohol (a trimethyl substituted primary hexanol) are cooled to 5 to 10 C. and are added to the P001; with continuous stirring at a rate so as to maintain a reaction-mass temperature of about 15 C. The reaction mixture is agitated and the temperature of the reaction mixture is allowed to come up to room temperature, thereafter the stirring is continued and the reaction mixture is placed under a vacuum (below 50 mm.) over a period of 2 hours thereby removing the hydrogen chloride gas which is evolved from the reaction.

An aqueous solution of sodium phenate is prepared by adding 592.2 g. of phenol to 840 cc. of water having dissolved therein 542.0 g. of 46.5% sodium hydroxide. The aqueous sodium phenate solution is cooled to 0 C. and the nonyl phosphoryl dichloride, prepared by the reaction of the nonyl alcohol and the POCls, is added to the aqueous sodium phenate solution at such at rate as to maintain a temperature below 5 C. After all of the nonyl phosphoryl dichloride has been added to the aqueous sodium phenate solution, the reaction mixture is agitated for a period of 3 hours and allowed to warm up to room temperature. When the agitation is stopped, the reaction mixture separates into an ester layer and an aqueous layer and the ester layer may be then separated from the aqueous layer by decantation. The ester layer is given successive washes with 2% NaOH solution and water and then dehydrated under vacuum at about 100 C. The yield, based on POCla, was

The nonyl diphenyl phosphate prepared as above described had the following properties:

Sp. gr. 25/25 C 1.074

Freezing point Below 0C.

Color Nearly water white EXAMPLE III Iso-octyl diphenyl phosphate 153.4 g. of POCla are cooled with stirring to about 10 C. in a glass lined closed reaction vessel. 130.2 g. of iso-octyl alcohol (G-methyi-lheptanol) are cooled to about 10 C. and added to the POCl; with continuous stirring and at a rate so as to maintain a reaction temperature of l0-14 C. The reaction mixture is continuously agitated and the temperature is gradually increased to 25 C. over a period of about one hour. While the stirring is continued, the reaction mixture is placed under a vacuum (below 50 mm.) for another 1 /2 hours to remove the hydrogen chloride gas which is evolved from the reaction. The reaction mixture now contains predominantly iso-octyl phosphoryl dichloride.

An aqueous sodium phenate solution is prepared by adding 197.5 g. of phenol to 280 cc. of water having dissolved therein 180.7 g. of 46.5% sodium hydroxide. The sodium phenate solution is cooled to about 5 C. and the iso-octyl phosphoryl dichloride is gradually added to the sodium phenate solution at such a rate as to maintain a temperature below 5 C. After all of the iso-octyl phosphoryl dichloride has been added to the sodium phenate solution, the tem- 11 peratmeisallowedtorisetoabnutfifland the reaction mixture stirred for an additional 3 hours. when the agitation is stoppe the reaction mixture separates into an ester layer and an aqueous layer and the ester layer is then separated from the aqueous layer by decantation. The ester layer is given successive washes with 25 NaOH solution and water and then dehydrated under vacuum at about 100 C. The yield, based on POCh. was 89%.

The iso-octyl diphenyl phosphate (ii-methylheptyl diphenyi phosphate) prepared as abov described had the following properties:

8p. 81'. 25l25 C 1.093

Freezing point Below 0.

color Nearly water white EXAMPLE IV z-mcthylpcntpl diphenul phosphate This ester was prepared by iirst reacting 102.1 g. of 2-methylpentanol with 158.4 g. of P0011. in the manner as described for the preparation of Z-ethylhexyl diphenyl phosphate, to form a 2-methylpentyl phosphoryl dichloride.

The 2-methylpentyl phosphoryl dichloride was then added to a cooled solution of 440 cc. of water and 243.6 g. or sodium phenate at such a rate as to maintain a reaction temperature below 5' C. After all of the 2-methyipentyl phosphoryl dichloride had been added to the sodium phenate solution, the reaction was finished oil and the 2- methylpentyl diphenyi phosphate was recovered in the same manner as was described in the milltion of z-ethylhexyl diphenyl phosphate. The yield of 2-methylpentyl diphenyl phosphate. based on POCls, was 88%, and this ester, in appearance, resembled the z-ethylhexyl diphenyl phosphate.

EXAMPLE V Decal diphentl phosphate The decyl alcohol used in this example was a chain decyl alcohol manufactured from the polymerization product of oleiins. While at the time of this application, the exact structure of the branched chain has not been definitely established, the fact that the alcohol does have a carbon atom branched chain primary alcohol structure has been definitely established. These alcohols, generally. are manufactured by polymerizing short chain oleflns to form a long chain polymeric oleflnic hydrocarhon. reacting this polymer with formaldehyde and hydrogenating the polymer-formaldehyde reaction product to form the alcohol.

16.! g. o! POCl: were cooled with stirring to about C. in a glass lined closed reaction vesael. 19.2 g. o! the above described decyl alcohol werecooledandaddedtothePOChatarat/eso as to maintain a reaction temperature of about 15' C. The reaction mixture is continuously agitated and the reaction temperature is allowed to rise to room temperature, thereafter the stirring is continued and the reaction is carried to completion to form the decyl phosphoryl dichloride by placing the reaction mixture under 'a vacuum (below 50 mm. Hg) over a period of 2 hours, thereby removing the hydrogen chloride gas which is evolved from the reaction.

An aqueous solution of sodium phenate, prepared by adding 98.8 g. of phenol to an alkaline nolutbn of 140 cc. of water and 89.6 g. o! 46.5% sodium hydroxide. is cooled to 0' C. and the decyl phosphoryl dichloride is added to the sodium phenate solution at such a rate as to maintain a reaction temperature 0! about 5'' C. After all of the decyl phosphoryl dichloride has been added, the reaction is carried to completion, the ester recovered and purified in the same manner as was described for the preparation of 2- ethylhexyl diphenyl phosphate.

The decyl diphenyl phosphate, prepared as above described, had the following properties:

Sp. gr. 25/25" 0 1.006

Freezing point Below 0 C.

Color Nearly water white The yield 01' decyl dlphenyl phosphate, based on POCh, was

Z-n-propulheptpl diphenpl phosphate Z-n-propylheptyl phcsphoryl dichloride was prepared by reacting 79.2 g. of z-n-propylheptanol with '16.! g. 0! P00]: in the manner described for the preparation of decyl phosphoryl dichloride. This z-n-propyl heptyl phosphoryl dichloride was then added to 368 g. 01' 33.3% sodium phenate solution at a temperature of 0 C. and the reaction carried to completion, the ester recovered in the manner as described tor the preparation or decyl diphenyi phosphate. The z-n-propyiheptyl diphenyl phosphate was thus prepared in a yield of 81.5% based on P001: and closely resembled the decyl diphenyl phosphate prepared in the previous example.

EXAMPLE VII Dodecpl diphenyl phosphate 118.5 cl a 12 carbon branched chain primary alcohol prepared from the polymerization products oi oleiins were cooled to about 20 C. and added to 97.8 g. oi POCh cooled to approximatehr 20' C. in a glass lined closed reaction vessel with continuous stirring and cooling so as to maintain a reaction temperature of about 20 C. The reaction mixture is agitated and the temperature is slowly raised to 30 to 40 C. and maintained at that temperature for one hour following the addition oi all the dodecyl alcohol; thereafter. temperature is raised to approximately 50 C. and the stirring continued for another hour. The hydrogen chloride gas which is evolved from the reaction is continuously removed by means of applying a vacuum to the reaction vessel.

Alter the reaction between the dodecyl alcohol and the P00 and the removal of the hydrogen chloride hi i been completed the dodecyl phosphoryl dichloride is transferred to a reactor containing about 420 g. 01' an aqueous sodium phenate solution, at a temperature below 5 0., prepared from 180 cc. of water, 126.2 g. of phenol and 115.4 g. of 46.5% soda lye. The dodecyl phosphoryl dichloride is added to the sodium phenate solution at such a rate as to maintain a temperature below 5 C. After all the dodecyi phosphoryl dichloride has been added to the sodium phenate solution, the reaction mixture is agitated for an hour and then with continuous stirring the temperature is gradually raised to 30 C. The reaction mixture is then allowed to stand until an ester layer and an aqueous layer form and the ester layer is separated from the aqueous layer. The ester is given successive washes with NaOH solution and water and then dehydrated under vacuum at C. The yield, based on POCla. was 85%.

13 EXAMPLE vm Z-ethylbutul diphenyl phosphate Z-ethylbutyl phosphoryl dichloride was prepared by adding 51.1 g. of 2-ethylbutanol to 76.7 g, of phosphorus oxychloride. cooled to 10 C., with continuous stirring and cooling and at such a rate as to maintain a reaction temperature of 10 to 15 C. The reaction mixture is held at 15 C. for an hour following the addition of the 2- ethylbutanol and thereafter the reaction temperature is raised to 25 C. and the reaction thereafter continuously stirred and held under 30 mm. Hg vacuum (to remove the HCl evolved) for an additional hour to complete the formation of the 2- ethylbutyl phosphoryl dichloride.

The Z-ethylbutyl phosphoryl dichloride was reacted with an aqueous sodium phenate solution cooled to C. and prepared by adding 98.8 g. of phenol to 140 cc. of water having dissolved therein 90,4 g. of 46.5% soda lye. The 2-ethylbutyl phosphoryl dichloride is added at a rate so as to maintain a reaction temperature below 5 C. and after all of the Z-ethylbutyl phosphoryl dichloride had been added, the reaction is finished off and the ester recovered in the manner described for the preparation of 2-ethylhexyl diphenyl phosphate. The yield of Z-ethylbutyl diphenyl phosphate, based on P001], was 89%, and the ester, in general appearance. closely resembled Z-methylpentyl diphenyl phosphate.

The 2-ethylbutyl diphenyl phosphate which was prepared in the above manner had the following properties:

sp. gr. 25 25 c 1.122 N 1.5152

EXAMPLE IX Z-ethylhezryl dz'cresyl phosphate 44.3 g. of POCla are cooled with stirring to about C. in a glass lined closed reaction vessel. 37.6 g. of Z-ethylhexanol are cooled to approximately C. and added to the POCls with continuous stirring and at a rate so as to maintain a reaction temperature of about 15 C. The reaction mixture is agitated and the reaction temperature of 15 C. is maintained for one hour following the addition of all the Z-ethylhexanol, thereafter the temperature is allowed to rise to approximately C. and the stirring continued for another hour. The hydrogen chloride gas which is evolved from the reaction is continuously removed by means of applying a vacuum to the reaction vessel.

After the reaction between the 2-ethylhexanol and the POCh and the removal of the hydrogen chloride have been completed, the 2-ethylhexyl phosphoryl dichloride is transferred to a reactor containing 246 g. of an aqueous solution, cooled to about 0 C. having a composition of 32.1% sodium cresylate. The 2-ethylhexyl phosphoryl dichloride is added to the aqueous sodium cresylate solution at such a rate as to maintain a temperature below 5 C. After all the 2-ethylhexyl phosphoryl dichloride has been added to the aqueous sodium cresylate solution, the reaction mixture is agitated for an hour and then with continuous stirring the temperature is gradually raised to C. The reaction mixture is then allowed to stand until an ester layer and an aqueous layer form and the ester layer is separated from the aqueous layer. The ester is given successive washes with 2% NaOH solution and water and 14 then dehydrated under vacuum at about 100" C. The yield, based on POCh, was

The 2-ethylhexyl dicresyl phosphate which was prepared by the above method had the following properties:

Sp. gr. 25/25 C 1.064

Ref. index 25 C 1.507

Boiling point at 5 mm Approx. 243 C.

Freezing point Below 0 C.

Color Nearly water white EXAMPLE X Iso-octyl dicresyl phosphate 153.4 g. of P001: are cooled with stirring to about 10 C. in a glass lined closed reaction vessel. 130.2 g. of iso-octyl alcohol are cooled to about 10 C. and added to the FCC]; with continuous stirring and cooling and at a rate so as to maintain a reaction temperature of 10 to 15 C. After all of the iso-octyl alcohol has been added to the reaction, the cooling means is removed and while the agitation is continued the reaction temperature is allowed to rise to room temperature. Thereafter, the stirring is continued while the reaction mixture is placed under a vacuum (below 50 mm. Hg) for 1 /2 hours to complete the reaction and removal of the hydrogen chloride gas which is evolved from the reaction. The product of the above reaction between iso-octyl alcohol and phosphorus oxychloride is iso-octyl phosphoryl dichloride.

An aqueous sodium cresylate solution is prepared by adding 227 g. of cresol to 280 cc. of water having dissolved therein 180.7 g. of 46.5% sodium hydroxide. This sodium cresylate solution is cooled to 0 to 3 C. and the above prepared iso-octyl phosphoryl dichloride is gradually added to the sodium cresylate solution at such a rate as to maintain a reaction temperature below 5 C. After all of the iso-octyl phosphoryl dichloride has been added to the sodium cresylate solution. the temperature is allowed to rise to about 25 C. and the reaction mixture stirred for an additional 3 hours, thereafter the iso-octyl dicresyl phosphate is recovered in the manner as described in the previous example. The yield of iso-octyl dicresyl phosphate, based on POCh, was 89%.

EXAMPLE XI Nonyl dicresyl phosphate 460.2 g. of POCl: are cooled with stirring to a temperature of 5 to 10 C. in a, glass lined closed reaction vessel. 432.8 g. of nonyl alcohol (a trimethyl substituted primary hexanol) are cooled to 5 to 10 C. and are added to the POC]; with continuous stirring and at a rate so as to main tain a reaction-mass temperature of about 15 C. The reaction mixture is agitated and the temperature of the reaction mixture is allowed to come up to room temperature, thereafter the stirring is continued and the reaction mixture is placed under a vacuum (below 50 mm.) over a period of 2 hours thereby removing the hydrogen chloride gas which is evolved from the reaction.

An aqueous solution of sodium cresylate is prepared by adding 686.7 g. of cresol to 840 cc. of water having dissolved therein 542.0 g. of 46.5% sodium hydroxide. The aqueous sodium cresylate solution is cooled to 0 C. and the nonyl phosphoryl dichloride, prepared by the reaction of the nonyl alcohol and the POCb, is added to the aqueous sodium cresylate solution at such a rate as to maintain a temperature below 5 C. After all of the nonyl phosphoryl dichloride has been added to the aqueous sodium cresylate solution, the reaction mixture is agitated for a period of 3 hours and allowed to warm up to room temperature. when the agitation is stopped. the reaction mixture separates into an ester layer and an aqueous layer and the ester layer may be then separated from the aqueous layer by decantation. The ester layer is given successive washes with 2% NaOH solution and water and then dehydrated under vacuum at about 100 C. The yield, based on P0013. was 89.7%.

EXAMPLE XII. Z-methulpentyl dicresyl phosphate 2-methyipentyl phosphoryl dichloride was prepared by adding 102.1 g. 01 2-methylpentanol, cooled to C., to 153.4 g. of phosphorus oxychloride cooled to 10 C. with stirring and cooling and at a rate so as to maintain a reaction temperature of 10 to C. After all of the 2-methyipentanoi had been added to the phosphorus oxychloride the reaction was carried to completion to form Z-methyipentyl phosphoryl dichloride in the same manner as was described for the preparation of iso-octyl phosphoryl dichloride.

The 2-methylpentyi phosphoryl dichloride was reacted with an aqueous sodium cresylate solution cooled to 3 C. and prepared by adding 227 g. of cresol to 280 cc. of water having dissolved therein 180.7 g. of 46.5% sodium hydroxide, at such a rate so as to maintain a reaction temperature of 3 to 5 C. After all of the Z-methylpentyi phosphoryl dichloride had been added to the sodium cresylate solution. the cooling means was removed and the reaction temperature allowed to rise to 22 C. Thereafter, the reaction was carried to completion by continuous agitation for about 1% hours. The 2 methylpentyl dicresyi phosphate was then recovered in the manner described for the preparation of nonyl dicresyl phosphate. The yield of Z-methylpentyl dicresyl Phosphate. based on POCh, was 90%.

The 2-methyipentyl dicresyl phosphate prepared as above described had the following properties:

Sp. gr. /25 C 1.081

Freezing point Below 0 C.

Color Nearly water white EXAMPLE XIH Z-ethulbutyl dicresyl phosphate 51.1 g. of z-ethylbutanoi were cooled to about 10 C. and slowly added to 76.7 g. of phosphorus oxychloride cooled to 10 C. in a closed glass lined reaction vessel at such a. rate as to maintain a reaction temperature of 12 to 14 C. After all of the 2-ethylbutanol had been added to the POCla, the reaction was carried to completion with the formation of 2-ethylbutyi phosphoryl dichloride in the same manner as was described for the preparation of 2-methylpentyl phosphoryi dichloride.

The 2-ethylbutyl phosphoryl dichloride was then added to an aqueous sodium cresylate solution. cooled to 0 C. and prepared by adding 113.4 g. of cresol to 230 g. of 18.2% sodium hydroxide solution. The Z-ethyibutyl phosphoryi dichloride is added to the sodium cresylate solution at such a rate as to maintain a reaction temperature of about 5 C. After all oi the 2-ethyibutyi phosphoryi dichloride was added, the reaction was carried to completion, and the ester recov- 16 ered in the same manner as was described lo the preparation or 2-ethylhexyl dicresyl phos phate. The yield of 2-ethylbutyl dicresyl phos phate, based on POCls, was substantially EXAMPLE XIV Dodecyl dicresyl phosphate 118:5 g. of a 12 carbon branched chain primary alcohol prepared from the polymerization prodnets of oleflns were cooled with stirring to about 20 C. in a glass lined closed reaction vessel. 97.8 g. of FCC]; was added. with continuous stirring and cooling. at a rate so as to maintain a reaction temperature of about 20 C. The reaction mixture is agitated and the temperature is slowly raised to 30 to 40 C. and maintained at that temperature for one hour following the addition of all the dodecyl alcohol; thereafter, the temperature is raised to approximately 50 C. and the stirring continued for another hour.

After the reaction between the dodecyl alcohol of the hydrogen chloride have been completed the dodecyl phosto a reactor 0011- EXAMPLE XV Z-n-propulheptul dicresyl phosphate 2-n-propylheptyl phosphoryl dichloride may be prepared by reacting at 15 to 20 C. 158.3 g. of 2- n-propylheptanol with EXAMPLE XVI 2-methulpentoryethill dicresyl phosphate 17 maintained for one hourjollowing the addition of all the ethylene glycol mono-z-methylpentyl ether, thereafter the temperature is allowed to rise to approximately 25 C. and the stirring continued for another hour. The hydrogen chloride gas which is evolved from the reaction is continuously removed by means of applying a. vacuum to the reaction vessel.

After the reaction between the ethylene glycol monc-2-methylpentyl ether and the P001: and the removal of the hydrogen chloride have been completed. the reaction mass containing 2- methylpentoxyethyl phosphoryl dichloride is transferred to a reactor containing 780 g. of an aqueous solution, cooled to about C., having a composition of 35% sodium cresylate. After the Z-methylpentoxyethyl phosphoryl dichloride has been added to the aqueous sodium cresylate solution, the reactionmixture is agitated for an hour and then with continuous stirring the temperature is gradually raised to 30 C. The reaction mixture is then allowed to stand until an ester layer and an aqueous layer form and the ester layer is separated from the aqueous layer. The ester is given successive washes with 2% NaOH solution and water and then dehydrated under vacuum at about 100 C. The yield, based on POCla, was 79%.

I EXAMPLE XVII Butoxyethyl diphenyl phosphate 153.4 g. of POCla are cooled with stirring to about C. in a glass lined closed reaction vessel. 118.1 g. of ethylene glycol monobutyl ether are cooled and added, with stirring, to the P001: over a period of one hour so as to maintain a reaction temperature of about 16 C. The stirring is continued for 1.5 hours after the ethylene glycol monobutyl ether has been added, the temperature being maintained at 15-20 C. and the reaction vessel being held under 50 mm. of vacuum to remove hydrogen chloride gas which is evolved from the reaction. The reaction mixture isdsubstantially butoxyethyl phosphoryl dichlori e.

The butoxyethyl phosphoryl dichloride is added to a sodium phenate solution consisting of 243.6 g. of sodium phenate and 450 cc. of water over a period of 2 hours while maintaining a reaction temperature of 03 C. Thereafter the temperature is allowed to rise to 20 C. and the stirring continued for about two additional hours. The reaction mixture is then allowed to stand until an ester layer and an aqueous layer form and the ester layer is then separated from the aqueous layer. The ester is given successive washes with 2% NaOH solution and water and then dehydrated under vacuum at about 100 C. The yield, based on POCla. was 89%.

The butoxyethyl diphenyl phosphate which was prepared in the above manner had the following properties:

Sp. gr. /25" C 1.146

Freezing point Below 0 C.

Color Essentially colorless EXAMPLE XVIII Z-ethylhexoxuethyl diphenyl phosphate 174 g. of ethylene glycol mono 2-ethylhexyl ether cooled to about 15 C. were slowly added with stirring to 153.4 g. of POCh, previously cooled to 15'' C. and contained in a closed glass lined reaction vessel, at such a rate so as to maintain a reaction temperature of 15 to 18 C. with continuous cooling of the reaction vessel. The reaction mixture is agitated for one hour following the addition of the ethylene glycol mono-2- ethylhexyl ether while maintaining a reaction temperature of 18 to 20 C., thereafter the temperature is allowed to rise to 25 C. and the stirring continued for another 1 hours while a vacuum of 50 mm. Hg. is applied to the reaction vessel to remove the hydrogen chloride gas which is evolved from the reaction. The reaction prodnot is 2-ethylhexoxyethyl phosphoryl dichloride.

The 2-ethylhexoxyethyl phosphoryl dichloride was added with stirring to about 695 g. oi a 35% sodium phenate solution cooled to 04 C. The reaction mixture is continuously cooled and the 2 ethylhexoxyethyl phosphoryi dichloride is added at a rate so as to maintain a reaction temperature of 0 to 5 C., which can be accomplished in 2% to 3 hours. Thereafter, the reaction temperature is allowed to rise to room temperature and the stirring continued for an additional 2 hours to finish oil the reaction. The reaction mixture is then allowed to stand until an ester layer or 2-ethylhexoxyethyl diphenyl phosphate separates from the aqueous layer and the ester is then separated from the aqueous layer by decantation. The ester is given successive washes with 2% NaOH solution and water and then dehydrated under vacuum at about C. The yield. based on POCla, was 84 EXAMPLE XDI Z-ethylhezomyethul dicresyl phosphate 2-ethylhexoxyethyl phosphoryl dichloride was prepared in the manner as was described for the preparation of 2-ethylhexoxyethyl diphenyl phosphate.

690 g. of a sodium cresylate solution was prepared by adding 227 g. of m-cresol to about 463 g. of an aqueous sodium hydroxide solution containing 84 g. of NaOH, cooled to about 3 C., and while the cooling was continued, the 2-ethylhexoxyethyl phosphoryl dichloride was added to the sodium cresylate solution with stirring and at such a rate as to maintain a reaction temperature of 0 to 5' C. The temperature of the reaction mass was then allowed to rise to room temperature while the stirring was continued and the reaction was completed in about two hours. The 2-ethylhexoxyethyl dicresyl phosphate, recovered in the manner as described for Z-ethylhexoxyethyl diphenyl phosphate, was obtained in a yield of 89 based on POCh.

EXAMPLE XX Z-n-propylheptoxyethul dicresyl phosphate 76.! g. of phosphorus oxychloride were cooled to 15 C. in a glass lined closed reaction vessel, and with continuous cooling of the reactor, 101 g. of ethylene glycol mono-2-n-propylheptyl ether were added with stirring to the phosphorus oxychloride at a rate so as to maintain a reaction temperature of 15 to 20 C. After all of the ethylene glycol mono-2-n-propylheptyl ether had been added, the agitation was continued while the temperature was raised to about 25 C., at which time a vacuum of 25 mm. Hg was applied to the reactor and maintained for about two hours to remove the hydrogen chloride evolved and carry the reaction to completion to form 2-n-propylheptoxyethyl phosphoryl dichloride.

An aqueous solution of sodium cresylate, prepared by adding 113.5 g. of cresol to an aqueous alkaline solution prepared by dissolving 89.8 g. of 46.5% soda lye in 140 cc. of water is cooled to C. and the 2-n-propylheptoxyethyl phosphoryl dichloride is added to the cooled sodium cresylate solution with stirring and at a rate so as to maintain a reaction temperature of about 5 C. There after, the reaction is finished of! by slowly raising the temperature to about 25 C. and stirring for 2% to 8 hours. The finished ester is then recovered in the manner described for the preparation of 2-ethylhexoxyethyl dioresyl phosphate. The yield of 2-n-propylheptoxyethyl dicresyl phosphate was 90%.

EXAMPIE XXI Dodecoryethyl diphenul phosphate 1b 200 g. 0! POCh, cooled to about 20 C. in a closed and continuously cooled reactor, 300 g. of ethylene glycol monododecyl ether were added, withstirringandataratesoastomaintaina reaction temperature of about 20 C. After all of the ethylene glycol monododecyl ether had been added to the F001;, the reaction mixture was agitated and the temperature slowly raised to and maintained at 30 to 40 C. for about one hour. Thereafter the temperature was raised to 50 C. and maintained at that temperature for an additional hourwhile the stirring was continued and a vacuum of 25 mm. Hg was applied to the reactor to remove the hydrogen chloride formed during the reaction. The product of this reaction was dodecoxyethyl phosphoryl dichloride.

A sodium phenate solution, prepared by reacting 257.5 g. of phenol with 650 g. of an aqueous caustic solution containing 109.3 g. of NaOH, was cooled to 5 C. and while the cooling of the sodium phenate solution was continued, the above pre pared dodecoxyethyl phosphoryl dichloride was slowly added to the cooled sodium phenate solutionwithstirringandataratesoastomaintain a reaction temperature of about 5' C. Thereafter, the temperature was slowly raised to 30 C. and the stirring continued for another hour, at which time the reaction was finished with the formation of dcdecoxyethyl diphenyl phosphate. when the stirring ofthe reaction mixture is stopped, the mixture separates into an aqueous layer and an ester layer. The ester was given successive washes with 2% NaOH solution and water and then dehydrated imder vacuum at about 100 C. The yield oi dodecoxyethyl diphenyl phosphate. based on POCh, was 04%. 0

EXAMPLE XXII Butoruethyl di (o-chlorophenyl) phosphate 153.4 g. (1.0 mol) of POCh are cooled with stirring to about C. in a glass lined closed reaction vessel. 118 g. (1.0 mol) of anhydrous ethylene glycol monobutyl ether which has been cooled to approximately 15 C. is added to the P001: with continuous stirring and at a rate so as to maintain a reaction temperature of about 15 C. The reaction mixture is agitated and by means of continuous stirring the reaction temperature of 15 C. is maintained for one hour following the addition of all of the ethylene glycol monobutyl ether, thereafter the temperature is allowed to rise to 25 C. and the stirring continued for another hour while the hydrogen chloride gas which is evolved from the reaction is continuously removed by means of applying a vacuum of 25 mm. E8 to the reaction vessel. The reaction product is butoxyetbyl phosphoryl dichloride.

A sodium o-chlorophenate was prepared by adding 282.3 g. (2.1' mols) oi o-chlorophenol (95.6%) to an aqueous alkaline solution prepared by dissolving 175.6 g. of 48% sodium hydroxide in 280 cc. of water. This solution of sodium o-chlorophenate is cooled to 3 C. and with continuous cooling 230.7 g. of the butoxyethyl phosphoryl dichloride are added to the sodium 0- chlorophenate solution at such a rate as to maintain a reaction temperature below 5 C. After all of the butoxyethyl phosphoryl dichloride has been added to the sodium o-chlorophenate solution, the reaction mixture is agitated for an additional hour and then, with continuous stirring, allowed to warm up to room temperature. The mixture is then allowed to stand until an ester layer of butoxyethyi di (o-chlorophenyl) phosphate and an aqueous layer form and the ester layer is then separated from the aqueous layer by decantation. The ester is given successive washes with 2% sodium hydroxide solution and water and then dehydrated under vacuum at about 100 C. The yield, based on 9001;, was 80.7%.

The butoiwethyl di (o-chlorophenyl) phosphate prepared in the above manner had the following properties:

Sp. gr. 25 25 c 1.25? n 1.52s

EXAMPLE XXIII z-ethylheryl di (o-chlorophenyl) phosphate 130.2 g. of 2-ethylhexanol were cooled with stirring to about 10 C. and added to 153.4 g. of P001: which were cooled to approximately 10 C. in aglass lined reactor with continuous stirring and at a rate so as to maintain a reaction temperature of 10-15 C. The reaction mixture was agitated and the temperature was slowly raised to 25' C. and maintained at that temperature for one hour following the addition of all the 2- ethylhexanol; thereafter the temperature was raised to approximately 30 C. and the stirring continued for another hour while the remaining hydrogen chloride gas which was evolved from the reaction was removed by means of applying a vacuum of mm. Hg to the reaction vessel. The product of the above reaction was 2-ethylhexyl phosphoryl dichloride.

168.0 g. of 49.8% sodium hydroxide solution were added to a mixture of 284.4 g. (2.1 mols) of 95.8% o-chlorophenol and 280 cc. of water to form an aqueous solution of sodium o-chlorophenate. This solution was stirred and cooled to about 5 C. and while the cooling and stirring was continued, the above prepared 2-ethy1hexylphosphoryl dichloride was slowly added to the cooled solution of sodium o-chlorophenate at a rate so that the reaction temperature below 5 C. could be maintained. After all the 2-ethylhexyl phosphoryl dichloride has been added to the sodium chlorophenate solution, the reaction mixture is agitated for an hour and then with continuous stirring the temperature is gradually raised to 30 C. The reaction mixture is then allowed to stand until an ester layer and an aqueous layer form and the ester layer is separated from the aqueous layer by decantation. The ester is given successive washes with 2% NaOH solution and water and then dehydrated under vacuum at about 100 C. The yield of 2 ethylhexyl di (0 chlorophenyi) phosphate. hasedcn POCh,was80%.

21 sum xxrv Tridecyl some! phosphate 120.1 g. of a 18 carbon branched chain primary iloohol prepared from the polymerization prodicts of oleiins were cooled to about 20 C. and idded to 02.0 g. of P061: cooled to about 20 C. n a glass lined closed reaction vessel with coninuous stirring and cooling so as to maintain a eaction temperature of about 20 C. The relction mixture was agitated and the temperature lowly raised to 30 to 40 C. and maintained at bat temperature for one hour following the addiion of all the tridecyl alcohol. The temperature was then raised to about 50 C. and the stirring :ontinued for another hour. The hydrogen chloide gas which was evolved from the reaction was :ontlnuously removed by means applying a racuum to the reaction vessel.

158.9 g. of the above prepared trldecyl phosihoryl dichloride were transferred to a reactor pntalning about 325 g. of an aqueous sodium ihenate solution. at a temperature below 15 C.. irepared from 140 cc. of water, 98.8 g. of phenol, ind 87.0 g. of 48.3% sodium hydroxide. The trilecyl phosphoryl dichloride was added to the lodium phenate solution at such a rate as to naintain a temperature between 11 and 14 C. liter all the tridecyl phosphoryl dichloride had leen added to the sodium phenate solution, the section was carried to completion. The reacion mixture was then allowed to, stand until an lster layer and an aqueous layer formed and the :ster layer was separated from the aqueous layer. the ester was given successive washes with NaOH olution and water and then dehydrated under 'acuum at 100 C. The yield. based on POCh. was 88.8%.

The tridecyl diphenyl phosphate prepared in he above manner, had the following properties:

Fp. gr. 25/25 C 1.0440

our point -45 1".

lolor Nearly water white iscosity at 100 F 97 .37 Universal Saybolt seconds iscosity at 210 F 38.77 Universal Baybolt seconds EXAMPLE XXV Tetrodecyl diphenpl phosphate 76.7 g. of P001: were cooled with stirring to a emperature of 5 to C. in a glass lined closed eaction vessel. 107.1 g. of a 14 carbon branched hain primary alcohol prepared from the polyuerization products of oleflns were cooled to 5 0 10 C. and added to the P001: with continuus stirring at a rate so as to maintain a reaction riass temperature of about 15 C. The reacion mixture was agitated and the temperature f the reaction mixture allowed to come up to com temperature, thereafter the stirring was ontinued and the reaction mixture placed under vacuum (below 50 mm.) over a period of 2 iours thereby removing the hydrogen chloride as which was evolved during the reaction.

An aqueous solution of sodium phenate was repared by adding 79.0 g. of phenol to 130 cc. l water having dissolved therein 69.7 g. of 48.3% odium hydroxide. The aqueous sodium phenate olution was cooled to about 5 C. and 132.5 g. of be above prepared tetradecyl phosphoryl dichlo lde was added to the aqueous sodium phenate solution over a, period of about two hours and at such a rate as to maintain a temperature between 5 C. and 15 C. After all of the tetradecyl phosphoryl dichloride was added the reaction was taken to completion and then allowed to stand and separate into an ester layer and an aqueous layer. The ester layer was removed and iven successive washes with a 2% NaOH solution and water and then dehydrated under vacuum at about C. The yield, based on POCh. was 87.1%.

The tetradebyl diphenyl phosphate prepared as above described had the following properties:

Sp. gr. 25l25 C 1.0382 N 1.5007 Pour point --40 1''. Color Nearly water white Viscosity at 100 F 106.82 Universal Saybolt seconds Viscosity at 210 1" 39.31 Universal Saybolt seconds EXAMPLE XXVI Octadecul dfphenyl phosphate The octadecyl alcohol used in this example 2-(1,3,3-trimethylbutyl) 5,7,7 trimethyl- 1 -00- tanol prepared from the polymerization products of oleflns.

76.7 g. of P001; were cooled with stirring to about 25 C. in a glass lined closed reaction vessel. 135.5 g. of the above described octadecyl alcohol were cooled and added to the POCl; at a rate so as to maintain a reaction temperature of about 25 C. The reaction mixture was continuously agitated and the temperature allowed to rise to room temperature and maintained at this temperature for an additional one hour stirring period during which time the hydrogen chloride gas evolved during the reaction was removed by means of applying a vacuum (below 30 mm. Hg) to the reaction vessel.

The octadecyl phosphoryl dichloride was then transferred to a reactor containing an aqueous sodium phenate solution cooled to 25 C. and prepared by adding 98.7 g. of phenol to 139 cc. of water having dissolved therein 90.5 g. of 46.5% sodium hydroxide. The octadecyl phosphoryl dichloride was added to the aqueous sodium phenate solution at such a rate as to maintain a temperature below 30 C. After all the octadecyl phosphoryl dichloride was added the reaction mixture was stirred for an additional three hours allowing the mixture to come to room temperature. 0n standing the reaction mixture separated lnto an aqueous layer and an ester layer. The ester layer was removed and given successive .washe with 2% NaOH solution and water and finally dehydrated under vacuum at about C. The yield of octadecyl diphenyl phosphate, based on POCls. was about 87%.

EXAMPLE XXVI! n-Hea-yl diphenpl phosphate 23 to remove the hydrogen chloride gas which 3 evolved.

An aqueous sodium phenate solution is prepared by adding 158.0 g. oi phenol to 200 cc. of water having dissolved therein 139.0 g. of 49.3% sodium hydroxide. The sodium phenate solution is cooled to about 5 C. and 175.4 g. of the hexyl phosphoryl dichloride previously prepared is gradually added to the sodium phenate solution maintaining a temperature below C. After all the hexyl phosphoryl dichloride has been added, the temperature is allowed to rise to about 25 C. and the reaction mixture stirred for an additional 5 hours. When the agitation is stopped, the mixture separates into an ester layer and an aqueous layer. The ester layer is recovered and given successive washes with a 2% sodium hydroxide solution and water and then further refined in accordance with the usual methods well known to those skilled in the art of refining phosphate esters. The yield, based on POCia, was 87.2%.

The n-hexyl diphenyl phosphate prepared as above described had the following properties:

Color Nearly water white Sp. gr. 25/25 C 1.1172 N 1.5062

EXAMPLE XXV'IIII n-Octvl diphenul phosphate This ester was prepared by first reacting 195.2 g. of n-octyl alcohol with 230.1 g. of POCla, in the manner as described for the preparation of a ethylhexyl phosphoryl dichloride, to form n-octyl phosphoryl dichloride.

246.0 g. of the above prepared n-octyl phosphoryl dichloride was then slowly added to an aqueous sodium phenate solution which had been prepared by dissolving 192.8 g. of phenol in 280 cc. of water, having dissolved therein 170.0 g. 0! 48.3% soda lye. This addition procedure was carried out at such a rate so as to maintain a reaction temperature below C. After all of the n-octyl phosphoryl dichloride had been added, the reaction mixture was stirred for an additional 3% hours while allowing the temperature of the mixture to rise to room temperature. The ester was then separated from the reaction mixture and purified in the same manner as was described in the preparation 01' 2-ethylhexyi diphenyl phosphate. The yield of n-octyl diphenyl phosphate, based on P001: was 89.5%.

The n-octyl diphenyi phosphate prepared as described above had the following properties:

Color Nearly water white Sp. gr. ,25/ C 1.0843 N 1.5082

EXAMPLE mm:

n-Decyl diphenul phosphate 158.1 g. of n-decyl alcohol were cooled to about 20 C. and added to 153.4 g. of POCl: cooled to approximately 20 C. in a glass lined closed reaction vessel with continuous stirring and cooling so as to maintain a reaction temperature of about 20 C. After all of the n-decyl alcohol had been added, while continuously agitating the mixture for an additional hour the temperature was slowly raised to about 50 C. and a vacuum applied to the system to remove the hydrogen chloride gas evolved from the reaction.

After the reaction between the n-decy1 alcohol and P001: had been completed, the reaction mixture containing n-decyl phosphoryl dichloridl was transferred to reactor containing about 197 g of phenol, 172 g. of 50% sodium hydroxide and 300 cc. of water at a temperature below 5 C The n-decyl phosphoryl dichloride wasadded a1 such a rate so as to maintain a reaction temperature below 5 C. After the addition had beer completed, the reaction mixture was allowed tc rise to room temperature with continuous stirring for an additional 2 hours. The mixture was then allowed to stand whereupon it separated intc an aqueous layer and an ester layer which was recovered. given successive washes with a sodium hydroxide solution and water and then further refined in accordance with the usual method: well known to those skilled in the art. The yield based on F0013. is 91.5%.

The n-decyl diphenyl phosphate prepared as herein described had the following properties:

Color Nearly water whit: N 1.5025 Sp. gr. 25l25 C 1.0627

EXAMPLE XXX Lauri/l dinhenyl phosphate Lauryl phosphoryl dichloride was prepared ir the manner described for the preparation oi n-decyl phosphoryl dichloride by reacting 139.5 g of lauryl alcohol with 115.1 g. of POCh while maintaining a reaction temperature of about 25' C. The lauryl phosphoryl dichloride thus obtained was added over a period of 1% hours anc at such a rate so as to maintain a temperaturl of about 25 C., to an aqueous sodium phenatc solution which had been prepared by dissolving 150.6 g. of phenol in 230 cc. of water having dissolved therein 128.0 g. of 50% sodium hydroxide After all of the lauryl phosphoryl dichloride had been added, the reaction mixture was stirred 1'01 an additional 3 hours. The mixture was then allowed to stand whereupon it separated into at aqueous layer and an ester layer. The ester layei was recovered, given successive washes with a sodium hydroxide solution and water to remove any partial esters and unreacted phenol, and then dehydrated under vacuum at about 110' C. The yield based upon POCI; was about 87%. The lauryl diphenyl phosphate prepared according tc the above procedure had the following properties:

EXAMPLE XXX! n-Heradeczll diphenyl phosphate 153.4 g. of P001: are cooled with stirring tc about 15 C. in a. glass lined closed reaction vessel. 242.4 g. of n-hexadecyl alcohol are heated tc about 50 to C. and added to the POCls with continuous stirring over a period of about 1% hours and at such a rate so as to maintain a reaction temperature of from 10 to 15 C. The reaction mass is then slowly heated to 26 C. and stirred for an additional hour while removing under vacuum the hydrogen chloride gas whicl: is evolved. The reaction mixture now contaim predominantly n-hexadecyl phOSDhOl'yI dichloride.

An aqueous sodium phenate solution is prepared by adding 197.5 g. of phenol to 280 cc. 01 water having dissolved therein 178.7 g. of 47% sodium hydroxide. The n-hexadecyl phosphory; dichloride is slowly added to the sodium phenati solution over a period or about 1 hour while maintaining a reaction temperature of about 25 C. After all of the reactant has been added, the reaction mixture is stirred for an additional 3 hours after which time the mixture is allowed to stand whereupon it separates into an ester layer and an aqueous layer. The ester layer is separated from the aqueous layer by decantation, given successive washes with 2% sodium hydroxide solution and water and then dehydrated under vacuum at about 105 C. The yield of n-hexadecyl diphenyl phosphate, based on POCI3, is 79.3%.

The n-hexadecyl diphenyl phosphate prepared as herein described had the following properties: Color Nearly water white N 1.4934 Sp. gr. 25/25 C 1.0122 Crystallizing point +13.7 C.

EXAMPLE XXXII n-Octadecul diphenul phosphate 153.4 g. of FCC]: are cooled with stirring to about 10 C. in a glass lined closed reaction vessel. 270 g. of powdered n-octadecyl alcohol are added to the POClJ with continuous stirring and at a rate so as to maintain a reaction temperature of about 25 C. The reaction mixture is continuously agitated over a period of about 1 hour. While the stirring is continued, the temperature is slowly raised to about 40 C. and the reaction mixture placed under a vacuum (below 50 mm.) for another 1 hours to remove the hydrogen chloride gas which is evolved from the reaction. The reaction mixture now contains predominantly n-octadecyl phosphoryl dichloride.

An aqueous sodium phenate solution is prepared by adding 197 g. of phenol to 300 cc. of water having dissolved therein 181 g. of 46.5% soda lye. The n-octadecyl phosphoryl dichloride is gradually added to the sodium phenate solution at such a rate as to maintain a temperature of about 30 C. After all of the reactant has been added, the temperature is raised to about 40 C. and the reaction mixture stirred for an additional 2 hours. When the agitation is stopped, the reaction mixture separates into an ester layer and an aqueous layer and the ester layer is then separated from the aqueous layer by decantation. The ester layer is given successive washes with 2% sodium hydroxide solution and water and then dehydrated under vacuum at about 100 C. thereby obtaining substantially pure n-octadecyl diphenyl phosphate.

EXAMPLE XXXIII n-Tetradecoxpethyl dicresyl phosphate 153.4 g. of P001: are cooled with stirring to about 10 C. in a glass lined closed reaction vessel. 258 g. of ethylene glycol mono-n-tetradecyl ether are cooled to approximately 15 C. and added to the P001; with continuous stirring and at a rate so as to maintain a reaction temperature of 20 C. The reaction mixture is agitated and the reaction temperature of 20 C. maintained for 1 hour following the addition of all the reactant. thereafter the temperature is allowed to rise to about 25 C. and the stirring continued for another hour. The hydrogen chloride gas which is evolved from the reaction is continuously removed by means of applying a vacuum to the reaction vessel.

The tetradecoxyethyl phosphoryl dichloride is transferred to a reactor containing 780 g. of an aqueous solution. cooled to about 0., having a composition of 35% sodium cresylate. After all of the reactant has been added to the aqueous sodium cresylate solution. the reaction mixture is agitated for 1 hours and then with continuous stirring the temperature is gradually raised to 30 C. The reaction mixture is then allowed to stand until an ester layer and an aqueous layer form. and the ester layer is separated from the aqueous layer. The ester is given successive washes with 9. 5001111111 hydroxide solution and water and then dehydrated under vacuum at about C. thereby obtaining n-tetradecoxyethyl dicresyi phosphate.

What is claimed is:

1. In a process for the preparation of monoalkyl diaryl phosphate esters of the type wherein R1 represents a radical selected from the group consisting of alkyl radicals terminating with a CH: group and containing at least 6 and not more than 18 carbon atoms and beta-alkoxyethyl radicals wherein the alkyl substituent contains at least 4 and not more than 18 carbon atoms and R2 is selected from the group consisting of phenyl, cresyl and chlorophenyl radicals, the steps comprising reacting a one molecular proportion of a primary aliphatic alcohol selected from the group consisting of primary aikyl alcohols wherein the alkyl radical contains at least 6 and not more than 18 carbon atoms and beta-alkoxyethyl alcohols wherein the alkyl substituent contains at least 4 and not more than 18 carbon atoms with a substantially one molecular proportion of phosphorus oxychloride while maintaining a reaction temperature between about +2 C. and about +25 C. until the reaction between the selected aliphatic alcohol and the phosphorus oxychloride is substantially complete and while removing the hydrogen chloride formed and thereafter continuing the removal of hydrogen chloride formed at a, temperature not exceeding 50 C., to form a monoalkyl phosphoryl dichloride and adding said monoalkyl phosphoryl dichloride to substantially two molecular proportions of a sodium arylate in an aqueous solution while maintainin a reaction temperature of l0 C. to +50 C., said sodium arylate being selected from the group consisting of sodium phenate, sodium cresylate. and sodium chlorophenate.

2. In a process for the preparation of monoalkyl diaryl phosphate esters of the type wherein R1 represents a radical selected from the group consisting of alkyl radicals terminating with a CH: group and containing at least 6 and not more than 18 carbon atoms and betaalkoxyethyl radicals wherein the alkyl substituent contains at least 4 and not more than 18 carbon atoms and R: is selected from the group consisting of phenyl, cresyl and chlorophenyl radicals, the steps comprising reacting a one molecular proportion of a primary aliphatic alcohol selected from the group consisting of primary alkyl alcohols wherein the alkyl radical contains at least 6 and not more than 18 carbon atoms and beta-alkoxyethyl alcohols wherein the alkyl substituent contains at least 4 and not more than 18 carbon atoms with a substantially one molecular proportion of phosphorus oxychloride while maintaining a reaction temperature between about +2 C. and about +25 C. until the reaction between the selected aliphatic alcohol and the phosphorus oxychloride is substantially complete and while removing the hydrogen chloride formed and thereafter continuing the removal oi the hydrogen chloride formed under a reduced pressure and at a temperature not exceeding 50 C., to form a monoallcyl phosphoryl dichloride and adding said monoalkyl phosphoryl dichloride to substantially two molecular proportions of a sodium arylate in an aqueous solution while maintaining a reaction temperature of -l' C. to +50 0.. said sodium arylate being selected irom the group consisting of sodium phenate, sodium cresylate, and sodium chlorophenate.

8. The process for the preparation of monoalkyl diaryl phosphate esters oi the type wherein R1 represents a radical selected from the group consisting of allryl radicals terminating with a CH: group and containing at least 6 and not more than 18 carbon atoms and beta-alkoxyethyl radicals wherein the alkyl substituent contains at least 4 and not more than 18 carbon atoms and R2 is selected from the group consisting of phenyl, cresyl and chlorophenyl radicals. comprising reacting a one molecular proportion of a primary aliphatic alcohol selected from the group consisting of primary aliryl alcohols wherein the alkyl radical contains at least 6 and not more than 18 carbon atoms and beta-alkoxyethyl alcohols wherein the alkyl substituent contains at least 4 and not more than 18 carbon atoms with a substantially one molecular proportion of phosphorus oxychloride while maintaining a reaction temperature between +2 C. and +25 C. and while removing the hydrogen chloride formed, to form a monoalkyl phosph oryl dichloride and add- Ing said monoallavl phosphoryl dichloride to substantially two molecular proportions of a sodium arylate in an aqueous solution while maintaining a reaction temperature of C. to +50 C., said sodium arylate being selected from the group consisting of sodium phenate, sodium cresylate, and sodium chlorophenate, and recovering the substantially pure monoalkyl diaryl ester of orthophosphorlc acid.

4. The process for the preparation of monoaikyl diaryl phosphate esters of the type wherein R1 represents a radical selected from the group consisting of alkyl radicals terminating with a CH: group and containing at least 6 and not more than 18 carbon atoms and beta-alkoxyethyl radicals wherein the alkyl substituent contains at least 4 and not more than 18 carbon atoms and R: is selected from the group 01' phenyl. cresyl, and chlorophenyl radicals, comprising reacting a one molecular proportion of a primary aliphatic alcohol selected from the group consisting of primary allryl alcohols wherein the alkyl radical contains at least 6 and not more than 18 carbon atoms and beta-alkoxyethyl alcohols wherein the allryl substituent contains at least 4 and not more than 18 carbon atoms with a substantially one molecular proportion of phosphorus oxychloride while maintaining a reaction temperature between +2 C. and +25 0. and while removing under reduced pressure the bydrogen chloride formed, to form a monoalhl phosphoryl dichloride and adding said monoalkyl phosphoryl dichloride to substantially two molecuiar proportions oi a sodium arylate in an aqueous solution while maintaining a reactiontemperature of 10 C. to +50 0.. said sodium arylate being selected from the Broup consisting of sodium phenate, sodium cresylate, and sodium chlorophenate, and recovering the substantially pure monoaibl diaryl ester of ortho-phosphoric a 5. In a process for the preparation of monoalkyl diary] phosphate esters of the type wherein R1 represents a radical selected from the group consisting of alkyl radicals terminating with a CH: group and containing at least 6 and not more than 18 carbon atoms and beta-alkoxyethyl radicals wherein the alkyl substituent contains at least 4 and not more than 18 carbon atoms and R2 is selected from the group consisting of phenyl, cresyl and chlorophenyl radicals, the steps comprising reacting a one molecular proportion of a primary aliphatic alcohol selected from the group consisting of primary alkyl alcohols wherein the alkyl radical contains at least 6 and not more than 18 carbon atoms and betaalkoxyethyl alcohols wherein the slim] substituent contains at least 4 and not more than 18 carbon atoms with a substantially one molecular proportion of phosphorus oxychloride while maintaining a reaction temperature between +2 C. and +25 C. and while removing under reduced pressure the hydrogen chloride formed, thereby forming a substantially pure monoalkyl phosphoryl dichloride. and adding the said monoaikyl phosphoryl dichloride to a substantially two molecular proportion of a sodium arylate in an aqueous solution while maintaining a reaction temperature of 0 C. to 25 0., said sodium arylate being selected from the group consistin of the sodium salts of phenol, cresol, and chlorophenol.

6. In a process for the preparation of monoalkyl diaryl phosphate esters ot the type wherein R1 represents a branched chain aihl radical containing at least 5 and not more than 17 carbon atoms and R: is selected from the group consisting of phenyl, cresyl, and chlorophenyl radicals, the steps comprising reacting a one molecular proportion of a primary branched chain alkyl alcohol containing at least 8 and not more than 18 carbon atoms with a substantially one molecular proportion of phosphorus oxychioride while maintaining a reaction temperature between +2 C. and +25 0. and while removing under reduced pressure the hydrogen chloride formed, thereby forming a substantially pure monoalbl phosphoryl dichloride, adding the said monoalkyl phosphoryl dichloride to a substantially two molecular proportion 01' a sodium arylate in an aqueous solution while maintaining a reaction temperature 01' 0 C. to 25 0., said sodium arylate being selected from the group consisting of the sodium salts of phenol. cresol. and chlorophenol.

7. In a process for the preparation of monoalkyl diaryl phosphate esters or the type wherein R1 represents a branched chain alkyl radical containing at least 5 and not more than 11 carbon atoms and R2 is selected from the group consisting of phenyl, cresyl, and chlorophenyl radicals, the steps comprising reacting a one molecular proportion 01 a primary, branched chain, alkyl alcohol containing at least 6 and not more than 12 carbon atoms with a substantially one molecular proportion oi phosphorus oxychloride while maintaining a reaction temperature between +2 C. and +25 0. and while removing under reduced pressure the hydrogen chloride formed, thereby forming a substantially pure monoalkyl phosphoryl dichloride, adding the said monoalkyl phosphoryl dichloride to a substantially two molecular proportion of a sodium arylate in an aqueous solution while maintaining a reaction temperature of C. to 25 C., said sodium arylate being selected from the group consisting oi the sodium salts of phenol, cresol, and chlorophenol.

8. In a process for the preparation of monoalkyl diaryl phosphate esters of the type wherein R1 represents a branched chain alkyl radical containing at least 5 and not more than 11 carbon atoms and R: is selected from the group consisting of phenyl, cresyl, and chlorophenyi radicals, the steps comprising reacting a one molecular proportion of a primary, branched chain, alkyl alcohol containing at least 6 and not more than 12 carbon atoms with a substantially one molecular proportion of phosphorus oxychloride while maintaining a reaction temperature between +2 C. and C. and while removing the hydrogen chloride formed, thereby forming a substantially pure monoalkyl phosphoryl dichloride, adding the said monoalkyl phosphoryi dichloride to a substantially two molecular proportion of a sodium arylate in an aqueous solution while maintaining a reaction temperature of 0 C. to 25 C., said sodium arylate being selected from the group consisting of the sodium salts of phenol, cresol, and chlorophenol.

9. The process described in claim 8, wherein the alkyl alcohol is a primary branched chain alkyl alcohol containing eight carbon atoms.

10. The process as described in claim 8, wherein the alkyl alcohol is 2-ethylhexanol and the sodium arylate is sodium phenate.

11. The process as described in claim 8, wherein the alkyl alcohol is 2-ethylhexanol and the sodium arylate is sodium para-cresylate.

12. The process as described in claim 8, wherein the alkyl alcohol is iso-octanol and the sodium arylate is sodium phenate.

13. The process for the preparation of monoalkyl diaryl phosphate esters oi the type wherein R1 represents an alkyl radical containing at least 5 and not more than 17 carbon atoms and R1 is selected from the group consisting of phenyl, cresyl, and chlorophenyl radicals, comprising reacting a one molecular proportion 01 a primary alkyl alcohol containing at least 6 and not more than 18 carbon atoms with a substantially one molecular proportion oi phosphorus oxychloride while maintaining a reaction temperature between +2 C. and +25 C., and while removing under reduced pressure the hydrogen chloride formed, thereby forming a substantially pure monoalkyl phosphoryl dichloride, adding the said monoalkyl phosphoryl dichloride to a substantially two molecular proportion oi. a sodium arylate in an aqueous solution while maintaining a reaction temperature of 0 C. to 25 C., said sodium arylate being selected from the group consisting of the sodium salts oi phenol, cresol, and chlorophenol, and separating the monoalkyl diaryl phosphate ester and washing said ester alternately with water and a dilute alkaline solution and subsequently drying said ester under vacuum at substantially C.

HARRY R. GAMRATH.

REFERENCES CITED The following references are of record in the file oi this patent:

UNITED STATES PATENTS Number Name Date 1,844,408 Nicolai Feb. 9, 1932 1,944,530 Schonburg Jan. 23, 1934 1,945,183 Clemmensen Jan. 30, 1934 2,005,619 Graves June 18, 1935 2,117,283 Bass May 17, 1938 OTHER REFERENCES Gerrard: Jour. Chem. Soc. (London) vol.

1940, page 1466.

Certificate of Correction Patent No. 2,504,121 April 18, 1950 HARRY R. GAMRATH It is hereby certified that error appears in the printed specification of the above numbered patent requiring correctlon as follows:

Column 8, line 24, for l0.50 F. read 1050 F.;

and that the said Letters Patent should be read as corrected above, so that the same may conform to the record of the case in the Patent Office. Signed and sealed this 17th day of October, A. D. 1950.

THOMAS F. MURPHY,

Assistant Commissioner of Patents. 

3. THE PROCESS FOR THE PREPARATION OF MONOALKYL DIARYL PHOSPHATE ESTERS OF THE TYPE 